I have an edit form that is taking about a minute to load. It has 4 or 5 tabs, fewer than 10 rules, and fewer 40 fields on the list. The new form (fewer rules) opens quickly. The only error showing in the console when I load the edit form is:
SCRIPT5022: Syntax error, unrecognized expression: #*
Any hints about how to troubleshoot the long load time?
As a point of interest, I have moved from using IE 11 to Firefox 60.x browser in order to speed load times on edit or new forms with serious lookups. This has decreased load times by 90% (from 3:15 to 0:20).
The edit form with the 3 minute load in IE uses DFFS (for a 47,000 item lookup) and SPServices (needed this for SharePoint OOTB lookup links and reverse proxy) to load a combined total of 67,000 items among three different dropdowns. Firefox Quantum’s superior rendering engine makes the load time tolerable.